This project is concerned with X-ray diffraction analysis of the structure of alkaline phosphatase from E. coli and bovine pancreatic ribonuclease-S and small molecule complexes with these enzymes. The immediate goal of the AP work is to extend the structure resolution from 7.7A 50 2.8A. The goals in the case of RNase-S are to refine the atomic resolution structure and phases, to examine temperature effects on the surface and solvent structure, to further examine dinucleotide binding, and to solve a second crystalline form. The project is also concerned with improving the methodology of protein diffraction and specifically this year to test a novel film method of data collection. This method consists of using an extended source with a stationary crystal and stationary film to produce a pseudo rotation pattern. Preliminary work has shown the method to be feasible and it has many potential advantages over current methods.